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Jessehk · Jul 8th, 2006, 7:40 PM

This trick is just cool.

Imagine being able to do things like this:

["Joe", "Sally", "Phil"].map(&:upcase) #=> ["JOE", "SALLY", "PHIL"]

With this snippet, you can. I did not think of this.

(Toggle Plain Text)

class Symbol
    def to_proc
        lambda { |obj, *args| obj.send(self, *args) }
    end
end

Example usage:

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require 'jesse_symbol' #where new code is stored

class Integer
    def square
        self * self
    end
end

p (1..10).map(&:square)

#or even
p (1..10).inject(&:+) #sum
p (1..10).inject(&:*) #product

Full explanation: http://blogs.pragprog.com/cgi-bin/pr...by/ToProc.rdoc

Jul 8th, 2006, 7:40 PM	#28
Jessehk The Oblivious One Join Date: May 2005 Location: Ontario, Canada Posts: 644 Rep Power: 4	This trick is just cool. Imagine being able to do things like this: (Toggle Plain Text) ["Joe", "Sally", "Phil"].map(&:upcase) #=> ["JOE", "SALLY", "PHIL"] ["Joe", "Sally", "Phil"].map(&:upcase) #=> ["JOE", "SALLY", "PHIL"] With this snippet, you can. I did *not* think of this. (Toggle Plain Text) class Symbol def to_proc lambda { \|obj, args\| obj.send(self, args) } end end class Symbol def to_proc lambda { \|obj, args\| obj.send(self, args) } end end Example usage: (Toggle Plain Text) require 'jesse_symbol' #where new code is stored class Integer def square self * self end end p (1..10).map(&:square) #or even p (1..10).inject(&:+) #sum p (1..10).inject(&:) #product require 'jesse_symbol' #where new code is stored class Integer def square self self end end p (1..10).map(&:square) #or even p (1..10).inject(&:+) #sum p (1..10).inject(&:*) #product Full explanation: http://blogs.pragprog.com/cgi-bin/pr...by/ToProc.rdoc __________________ Dr. Zoidberg: [ecstatic] I'm going to a movie... with FRIENDS!